Annealing-furnace.



W. A. WUUD 81 W. S. ROCKWELL.

ANNEALING FURNACE.

APPLICATION mu) APR.1, 1911.

lamnt 1 D00. 17, 1918.

2 QIEEISAHEEI I.

W. A. WOOD (I; W. S. ROCKWELL.

/ ANNEALING FURNACE.

APPLICATION FILED APR. I6, I917. N 1,288,353. 12mm m 11,1918.

2 SHEETS-SHEEI 2.

IIIII WILLIAM A. WOOD, OF DUNELLEN, NEW JERSEY, AND WALTER S. ROCKWELL, 013 NEW YORK, N. Y., ASSIGNORS T0 w. s. ROCKWELL COMPANY, on NEW YORK, n. Y., A

CORPORATION OF NEW JERSEY.

ANNEALING-FURNACE.

Specification of Letters Patent.

Patented Dec. 17, 1918.

To all whom it may concern:

Be it known that we, WILLIAM A. Wool), residing at Dunellen, county of Middlesex, and State of New Jersey, and WALTER S. lRocKwnLL, residing at 300 West 106" street, New York, county of New York, and State of New York, have invented certain new and useful Improvements in Annealing-Furnaces, fully described and represented in the following specification and the accomoanying drawings, forming a part of the same.

This invention relates to that class of furnaces in which metallic articles are heated in a non-oxidizing atmosphere, and are discharged directly into a tank of Water in order to cool them, thus avoiding rusting or tarnishing.

Such furnaces are especially applicable to the heating of metals or metallic articles for the purpose of annealing or softening the same; and the object of the present invention is to obviate the necessity of using a closed retort to maintain a non-oxidizing atmosphere during the heating operation, and also to obviate the necessity of employing a water-seal at the inlet and outlet of the heating-chamber to maintain such an atmosphere therein.

These objects are attained, first, by heating the metals in a furnace-chamber which is supplied with the hot products of combustion containing no excess oxygen from oil or gasburners, thus applying theheat directly to the metallic articles instead of to the outer wall of a retort or mufile. Second, securing a non-oxidizing atmosphere in such heating-chamber by the continuous introduction of such products of combustion; and third, by extending hoods from the opposite ends of the heating-chamber directly into proximity to the surface of water in suitable tanks, but leaving an interspace from which the gases escape, and which are continuously poured into the heating-chamher by the fuel lburners.

Any access of air to the interior of the hoods or the heating-chamber is thus prevented without the necessity of employing a water-seal. With such construction, a conveyer-chain may be arranged in the usual manner to carry the metallic articles through the water of the inlet-tank into the inletof the heating-chamber, then through such chamber, and finally from the outlet into the water of the outlet-tank, which cools them below oxidizing temperature before their removal therefrom.

The articles while passing through the heating-chamber are exposed to the direct contact of the highly heated products of combustion, which heat them much more quickly and economically than is possible when they are moved through a closed retort, and the articles may be moved more rapidly and the capacity of the furnace, per hour or day, thus greatly increased. While entering and leaving the hood, the articles also pass through a current of heated gases forced out of the mouths of the hoods, and are thus wholly protected from oxidization while entering and leaving the heatingcham'ber.

The invention will be understood by reference to the annexed drawing, in which Figure 1 is a plan of the furnace with the water-tank and conveyer at each end; Fig. 2

is a longitudinal section through the body of the furnace, hoods, tanks and driving mechanism; Fig. 3 is a cross section on line 33 in Fig 1; and Fig. 4 is a cross section of the hood and tank on line H in Fig. 1; Fig. 5 is a side elevation of the tank next the end of the hood. Figs. 3 to 5 are drawn on a larger scale than the other figures. Fig. 6 shows the outlet-pipe h in its relation to the water level.

A designates the brick body of the furnace containing the heating-chamber a into which the products of combustion are, continuously poured through fines a from combustion-chambers B below the heatingchamber, which combustion chambers are provided with fuel-burners b. The chamber is provided with inlet-doorway o and outletdoorway c. Watertanks (Z and d are supported near the inlet and outlet-ends of the chamber and the water level to maintained therein below the bottom line a of the heating-cham'ber.

Hoodsc and e are inclined downwardly from the doorways c and c nearly to the surface to of the water in the respective tanks 61 and cl, leaving a space 7 between the lower edges or mouths of such hoods and the Water, for-the escape of the products of combustion.

In practice, the heating-chamber is not provided with any other outlet for the prodnote cit-combustion, and the rate at which the products are permitted to escape may be varied by varying the water level '21:. A

chain-conveyor having upper and lower members C and C is shown extended through the water in the tanks and over guide wheels D and driving and return-pulleys E, E.

below the heating-chamber. The tanks and conveyor are extended beyond the hoods far enough to apply and remove the articles to be transported. Each tank is supplied with water by an inlet-pipe g, and means for varying the level of the water is provided, as shown in F igs. 4: and 5, in the form of an adjustable outlet-pipe h which is hinged to a wastepipeh below the surface of the water andcan, by swinging, have its mouth adjusted at the desired water level. A handle 7L projects upward from the T it which is employed to form the outlet to the pipe h, and a notched segment h is shown upon the side of the hood c in F 5, as it holds the handle in any adjusted position. The outlet pipe thus maintains the water level at a certain distance below the mouths of the hoods.

The pipe it issho'wn in Fig. 5 in full lines in an upright position maintaining the water level to in the tanks quite close to the edges of the hoods, and it, is also in Fig. 5 shown in dotted lines tipped suiliciently to lower the outlet and the water level to the short dotted line w. Fig. 6 shows the pipe it upon a larger scale, so that the effect of the outlet a in maintaining the water-level at a certain point is more readily apparent.

By extending; the open ends of the hoods below the floor-line oi the heatinghhamber, the air is unable to enter the hoods because it is heavier than the hot gases, pressing outward, therein, and inlet and outlet air-currents cannot therefore establish themselves in the hoods as they could in an open doorway or in a hood above the door level oi the chamber.

The variations of the tanks water level permit the adjustment of the spaces f to discharge more or less of the products of combustion from the heating-chamber a, and thus in some measure act as dampers to vary the temperature maintained in such chamber.

The direct heating oi the chamber a by the hot products of combustion permits the employment of those products to prevent the inlet of air at either end of the furnacechamber, and thus prevent the access ct atmospheric air to the chamber as efiectively as a water-seal.

insects By conducting the heated products of combustion through the heating-chamber they are brought into direct contact with the articles to be heated and thus heat them more rapidly and effectively than is possible in a retort.

The combustion-chambers are constructed under several parts of the heating-chamber, and thus keep the floor of the chamber as hot as any other part, and the flues a are extended from the combustion-chamber into the heating-chamber at various points throughout its length so that the temperature is uniform in all parts of the heatingchamber.

Such details of construction, and any others-Which promote'the heating of the chamber a, may be employed without affooting this invention, as they are not essen tial to its operation.

it is, however, to be understood that the burners are so regulated, and the supply of air for the combustion of the fuel, as to produce a non-oxidizing atmosphere in the heating-chamber and thus prevent any tarnishing or oxidizing of the articles which may be conveyed to the chamber.

The non-oxidizing atmosphere formed by such products of combustion is effectively maintained without the use of a water-seal, by the continuous influx of products of combustion into the heating-chamber, which inflHX produces a constant eiilux of such prod ucts from the spaces f at the mouths or open ends of the hoods, and which spaces are located below the level of the beatings-hamber floor, so that the gravity of the atmosphere and the relative levity of the products combustion prevent any tendency to an upward movement of the air into the hood. non-oxidizing protective atmosphere is thus maintained at the mouth of each hood, spreading upon the surface of the water so as to protect the articles which pass to or from the water into or out of the hood.

will thus be seen that although there is no water-seal at the open mouths of the hoods, and the articles to be heated are passed between the water and the hoods without the protection of a water-seal, they are nevertheless prevented from any exposure to or contact with the atmosphere, by the current of non-osidizing'gases which is continuously discharged from the mouths of the hoods into contact with the water.

Such protection of the articles from the atmosphere while passing to or from the water into or out of the hoods, is a distinguishing feature or" this invention, and is therefore claimed herein.

Having thus set forth the nature or" the invention what is claimed herein is:

1. A furnace having a heating-chamber with non-oxidizing products of combustion supplied thereto, hoods upon the ends of such heating-chamber extended downward below the floor-level of the chamber, means for controlling the area of the discharge of the said products of combustion from the mouths of the hoods, and a conveyer operating to move the articles to be heated through the heating-chamber into and out of the hoods through the products of combustion below their open mouths.

2. A furnace having a heating-chamber with non-oxidizing products of combustion supplied thereto, hoods upon the ends of such heating-chamber extended downwardly below the floor of the chamber, water surfaces in proximity to the lower edges of the hoods, and means for varying the level of the water to vary the discharge of the gases from the said hoods.

3. An annealing furnace having an annealing chamber directly heated by the products of combustion from one or more fuel-burners, water-tanks near the inlet and outlet-ends of the furnace, and hoods ex: tended from the opposite ends of the heating-chamber downward into proximity to the surface of the water in the said tanks, the space between the hoods and the water surfaces being adjusted to permit the escape of the products of combustion in the desired degree.

4. An annealing furnace having an annealing-chamber with non-oxidizing products of combustion supplied thereto, water tanks near the inlet and outlet-ends of the furnace, and hoods extended from the opposite ends of the heating-chamber downward into proximity of the surface of the water in the said tanks, the space between the hoods and the water-surfaces being adjusted to permit the escape of the products of combustion in the desired degree, and a conveyer operating to move the articles to be heated to and from the water and through the products of combustion below the hoods into and out of the said hoods and through the said annealing chamber.

In testimony whereof we have hereunto set our hands.

WILLIAM A. \VOOD. WALTER S. ROCKWELL. 

